Igniting apparatus for explosive-engines.



B, P. STEWART. TGNITING APPARATUS FOR EXPLOSIVE ENGINES. APPLIOAT'ION FILED AUG. s, 1908.

Patented Now/.16, 1909.

2 SHEETS-SHEET l. 1li' J9 1,5

5.1". STEWART. JGNITING APPARATUS FOR EXPLOSIVE ENGINES. APPLIUATIOH FILED AUG. S. 1908.

@@gm Patented Nov. 16, 1999.

INED

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' paratus being illustratedin diagram. Fim

BENJAMIN E. STEWART,

OF CHICAGO, ILLINOIS.

IGNITNG AFPARATUS FOR-EXPLOSIVE-EN GINES.

Qlfltl' Application filed August 8,

Specication of Letters Patent. ,'Pzrtgnted Nov. 16,' 1909.

1908.. Serial No. 447,621.

To all whom it may concern.: 4

Be it known that l, BENJAMIN F. STEW- ART, a citizen of the United States, and resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful In'iprovementsin lgniting Apparatus for EXplosive-llngines, ot' which the following is a specification, and which are illustrated in the accoi'npaiiying drawings, orming a part thereof.

The invention relates to apparatus for igniting the fuel charge in explosive engines, more particularly those explosive engines of the two-eycle type having a plurality of cylinders wherein provision is made for eX- ploding a charge ot luel in cach of the cylinders ot' the engine at every strolie of the iiston therein. l

The invention contemplates the ignition of the fuel charge in each cylinder oit an explosive engine comprising a plurality of power cylinders by means of an electrical spark projected from an electrode entering the chamber or' the cylinder through a side Wall thereof when the electrode is apl proachcd by the piston, the several elec trodes and the pistons for all of the cylinders being in the saine electric circuit tvhereby the distribution' ot' the electric current to the several cylinders is eil'ected by the movement ot' the pistons within the'cylii'idcrs toward and awayv from the corresponding electrodes. In order that thc time at which each of the electrodes is approached to Within a .suitable distance for the passage ot' a spark by the corresponding piston, during the cycle of n'iovcnient olf the piston Within the cylinder, may be adjusted, provision is preferably made for longitudinally shifting the electrodes within the cylinders.

The object of the invention is to provide means ot' simple and improved construction for igniting the explosive charge of gas engines at a predetermined time with reference to the position oil. the piston Within the engine cylinder without the use of a mechanically operated electrical switch commonly termed the timer f ln the accompanying drawings z-Figure 1 is a plan sectional view of a multi plc cylinder gas engine equipped witlrignitipg apparatus provided by the invcntiomthe plane of the section being indicated by the line 1-1 on Fig. 5 and parts of the igniting ap- 2 is e. detail sectional View of the engine taken on the line 2 2 of F ig. 5. Fig. 3 is similar to a detail of Fig. 2 showing one of the electrodes of the igniting apparatus drawn to a larger scale. Fig.- 4 is an end elevation ot the parts shown in- Fig. 3, and

` Fig. 5 is a side elevation of the engine illustrated in Fig. 1, some of the parts being shown in central vertical section. v

The engine illustrated in the drawings comprises a plurality of power cylinders designated 10, 11, 12, and 13 respectively, the walls ol the seyeral cylinders being east. integral and being inclosed by an integral jacket 14. 'A piston 15 reciprocates Within each of the cylinders 10, l1, 12 and 13, all of such pistons being connected by pitm'en 1G to a crank shaft 17 the cranks 17, 17", 17C, 17, of which are preferably so disposed about the shaft that the pistons 15 approach the inner ends of the cylinders 10, 11, 12 and 1.3 successively at regular intervals during the rotation of the-shaft. As shown, the cranks 17a, 17h, 17C and 17 are angularly spaced about the crank-shaft 17 at intervals of ninety degrees, whereby one of the four pistons 15 of the engine reaches the limit of its instroke at each quarter revolution of the crank shaft.

A casing 1S, secured by bolts 19 to a flange formed upon the Walls of the power cylinders 10, 11., 12 and 13 and the Jacket. 14 in closes the cranks of 'the crank shaft. 17, a separate compartment, as 20, being provided within the casing-,at the foot of each of the power cylinders l0, 11, 12 and 13. During the opera-tion o .t' the engine an explosive charge is compressed Within cach of the conn'iartments 2() of the crank case 18 during the advance ot' the piston 15 in the power cylinder communicating therewith. llf'hen the piston reaches the end of its out stroke this charge is delivered to the space behind the piston through a Vduct 2l leading through the Wall of the cylinder to a Jort opening 22 cont-rolled by the piston. his incoming charge' sweeps the products if combustion of the last preceding charle from thev chamber of the cylinder througn an exhaust port 28 also controlled by tire piston and is itself deflected toward the head of the cylinder by a projection or battle 24 formed upon the head of the piston 15 in front of the port opening 22.

- Means are rovided for electrically igniting the explltisive chargev delivered to each of the power cylinders 10, 11, 12 and 13 in l the sleeve 31.

the manner .just described, when the piston again approaches the head of the cylinder. To this end an electrode 26 preferably insulated from the wall of the cylinder and constitutin one of the terminals of an electrical circuit which is supplied with cur'- rent of suiiicient tension to cause a spark to pass over a short gap in the circuit, as from an induction coil 43, projects into the chamber of each of the cylinders of the engine to such a position that an appurtenance of the engine piston 15, asy the vertical faceof the baille 24 approaches it for the passage of a spark, when the piston approaches the end of its inward stroke. As shown each of the pistons 15 has electrical connection with the circuit25 by reason of one of the circuit Wires being connected to the wall of the en gine at 39.

Preferably the electrodes 26 are directed laterally into the chambers of the cylinders 10, 11, l2 and 13 and the vertical faces of the baiiies 24 move in a plane beyond the ends of the electrodes, the relation of these parts being such that a spark will be formed in each of the cylinders by the current impressed upon the circuit 25 only when the face ofthe baille plate 24 reaches the level of the corresponding electrode 26 and such a spark 'will continue to pass between these members for as long as any part of the battle plate 24 remains directly 1n front of the electrode 26.

The time when' a spark will begin to pass in each of the cylinders may be varied by vertically shifting the electrodes 26 within the cylinders. As shown each of the electrodes 26 is eccentrically mounted upon the end of a rotatable shaft 27 which projects 'through the side wall of the cylinder and the jacket 14 and carries upon its outer end a crank arm 28. Each of the shafts 27 is preferably carried by a removable plug 29,

Figs 3 and 4, adapted to enter a screiv threaded aperture 30 formed in the wall of the cylinden Preferably the shaft 27 is journaled in a sleeve 31 which in turn is supported within the plug 29 by being surrounded b a quantity of insulating matcrial 32 suc i as a plurality of ringsor washers of mica. This insulating material is clamped in position on the sleeve 31 between a fiange 33 formed on the inner end of the sleeve and a nut 34 running on the sleeve adjacent its outer end, that part ofthe insulating material 32 adjacent each of the ends of the sleeve being of greater diameter than the intervening portions as indicated at 35-36 for gripping the ends of the plug 29 and thus firmly uniting the parts whenv the insulating material is compressed by the application of the nut 34 to the outer end of A head 37 is formed on the inner end gf the shaft 27 for carrying the electrode 26. les shown this head is held in 'I frictional electrical contact with the inner flanged end of the sleeve 31 by means of the crank arm 28 which vis preferablyl adjustably secured to the outer end of the shaft 27 by anut 38 for engaging the outer end of thel sleeve 31.

In order that the shafts 27 at eachr of the cylinders 10, 11, 12 and 13 of the engine may be rotatedfor simultaneously adjust` a engine if the corresponding crank arm 28 be first disconnected from the rod 46 by the removal of the screw bolt 48.

Preferably the electric circuit 25 serves for supplying current to the electrodes 26 of all of the cylinders of the engine, one of the circuit wires being connectedto that of one of the cylinders as 13, Fig. 1, by being clamped between the nut 34 employed for securing the parts carried by the plug 29 in assembled position and a secondnut 40 running on the sleeve 31. The electrodes 26 for all ofthe other cylinders of the engine have electrical connection with the same branch of the circuit 25 as the electrode 26 of the cylinder 13 through the rod 46 and cranks 28 mounted upon the outer ends of the shaft 27. As shown current is supplied to the induction coil 43 from a` storage battery '45, asimple switch 47 being provided in the primary circuit of the induction coil for interrupting the flow of current from the battery when the engine is not in operation.

During the operation of the engine current will be continuously supplied to the in duction coil 43 from the battery 45, the secondary current from the coil being distributed to the several cylinders of the engine for the formation of a spark in each cylinder at the proper time by .the movement of the engine pistons into and out of sparking ositions in front ofthe electrodes 26. hen each of the electrodes 26 is in the adjusted position illustrated by full lines in Fig. 4 of the. drawings the ballie 24 formed upon the head of the pistons 15 will, not move to a position in front of the electrode for the passage of a spark, until the piston reaches the end of the inward stroke. lf however, the rod 46 be shifted to move the electrodes to the position represented b, dotted lines' in Fig. .4 or to an intermefiate position b turning the shaft 27 the baille 24 within eac of the cylinders will move in front of one of the electrodes-26ffor the' passage of a spark sov lso

before the piston reaches the end of its inward stroke and will remain in frontl of the electrode until after the piston has begun its outward stroke. Such an adjustment in position ofthe electrodes 26 will ordinarily be accompanied by a high rate of speed of the engine butv an ignition of each charge of fuel within the cylinder will nevertheless be insured by reason of the baffle 24 being in sparking position in front of the electrode 9G during'a considerable period.

The baille 24 formed upon the pistons of two-cycle gas engines is preferably formed witha fiat vertical faceas shown and for this rea-son provides a convenient part of the engine piston for coperatingI with the electrodel 26 for the formation of a spark, for while the electrode 26 is moved for adjustment through an arc by rotating the shaft 27, the horizontal distance from the end of the electrode to the face of the baille remains the same.

lI claim as my inventionl:-

l. In a gas engine in combination, a. cylin der, a piston reciprocable within the cylind'er, a projection formed on the head of the piston having a plane face parallel to the direction oi' the movement of the iston and adjacent a side wall of the cylin er, an insulated rotatable spindle enteringV the chamber ot' the cylinder through a side wall thereof, and an electrode coperating -With the face of the projection .on the piston mounted on the inner end lof the spindle out of line with the axis of rotation thereof.

2. In a gas engine, in combination, a plurality of cylinders, an electric circuit continuously supplied with current, a sparking electrode within the chamber of each of the cylinders, all of the electrodes being eleceach of the cylinders at each cycle of movement of the piston therein.

'3. In a gas engine, in'eombination, a cylinder, a sparking electrode within the chamber of the cylinder, a piston reciprocable within the cylinder toward and away from the electrode but never contacting therewith,

an electric circuit of `which said electrode and said piston constitute the terminals, said electric clrcuit being continuously supplied with current, and lever-operated means for shifting the electrode within the cylinder longitudinally thereof whereby the time of relative approachlbetween the piston and electrode to sparking position 1s changed with respect tothe cycle of movement of the piston within the cylinder.

l BENJAMN F. STEWART. 'Witnesses:

CHARLES B. GILLsoN, Lome K. GILLsoN. 

